2027 ICD-10-CM Diagnosis Code K90.81Whipple's disease

ICD-10-CM Codes›K00–K95›K90-K95›K90

ICD-10-CM K90.81
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

K90.81 is a billable ICD-10-CM diagnosis code for Whipple's disease. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 393 through 395. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 1 closely related codes. Coders also document this condition as central nervous system demyelination due to Whipple disease. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified gastrointestinal disorders.

K90.81 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 66 for payment year 2027.

Code Identity

ICD-10-CM Code
K90.81
Billable Status
Yes — Valid for Submission
Code Describes
Whipple's disease
Short Description
Whipple's disease
Same as the full description in the CMS dataset.
Parent Code
K90.8
Other intestinal malabsorption

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK90-K95Other diseases of the digestive system
CategoryK90Intestinal malabsorption
This CodeK90.81Whipple's disease

Medicare Risk Adjustment (HCC)Billing

K90.81 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
no payment category in the model that pays 100% of MA risk scores
Prior Model (CMS-HCC V24)
Not mapped under V24
this diagnosis newly risk-adjusts under the V28 model
Part D (RxHCC)
RxHCC 66 — Pancreatic Disorders and Intestinal Malabsorption, Except Pancreatitis
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Central nervous system demyelination due to Whipple disease
  • Dementia due to Whipple disease
  • Infection caused by Tropheryma
  • Malabsorption caused by infective agent
  • Neuro - Whipple's disease
  • Seronegative arthritis secondary to Whipple's disease
  • Whipple's disease

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to K90.81: its own notes plus those printed at K90 and Chapter 11. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From K90 Intestinal malabsorption applies to 13 codes
  • intestinal malabsorption following gastrointestinal surgery (K91.2)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 11 (K00-K95) Diseases of the digestive system applies to 863 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name K90.81, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming K90.81: they are not reported together with it, unless the two conditions are unrelated.

  • E88.1 Lipodystrophy, not elsewhere classified
    Whipple's disease (K90.81)
  • Block E40-E46 Malnutrition
    intestinal malabsorption (K90.-) names K90.-, which includes this code
  • K59 Other functional intestinal disorders
    intestinal malabsorption (K90.-) names K90.-, which includes this code

Code First 1

These codes say to code first a condition named in the note, and K90.81 is one of the conditions named.

  • M14.8 Arthropathies in other specified diseases classified elsewhere
    Whipple's disease (K90.81)

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR DIG025
Other specified and unspecified gastrointestinal disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Whipple Disease

    a chronic systemic infection by a gram-positive bacterium, tropheryma whippelii, mainly affecting the small intestine but also the joints; cardiovascular system; and the central nervous system. the disease is characterized by fat deposits in the intestinal mucosa and lymph nodes, malabsorption, diarrhea with fatty stools, malnutrition, and arthritis.

Patient EducationClinical

Malabsorption Syndromes

Your small intestine does most of the digesting of the foods you eat. If you have a malabsorption syndrome, your small intestine cannot absorb nutrients from foods.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert K90.81 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
040.2 Whipple's disease
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About K90.81Overview

What is the ICD-10 code for Whipple's disease?

The ICD-10-CM code for Whipple's disease is K90.81 (sometimes written as K9081). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is K90.81 (Other intestinal malabsorption) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report Whipple's disease on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does K90.81 group to?

When Whipple's disease is the principal diagnosis on an inpatient stay, it groups to MS-DRG 394, 395, 393, with relative weights from 0.6379 to 1.5877 depending on complications. Higher weights mean higher Medicare reimbursement.

Is K90.81 a CC or MCC?

CMS lists K90.81 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 1 closely related codes in its exclusion list.

Can K90.81 be reported with K91.2?

Not as a rule. The Excludes1 note at K90, which applies to K90.81, lists "intestinal malabsorption following gastrointestinal surgery (K91.2)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does K90.81 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage: K90.81 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 66 (Pancreatic Disorders and Intestinal Malabsorption, Except Pancreatitis).